The present invention pertains to the production of small embroidery pieces such as patch pockets and the like on muti-head embroidery machines. Such machines, as illustrated in the U.S. Pat. No. 2,091,727 to Bohmann et al, include a plurality of embroidery heads arranged on some type of common support mechanism. Each head includes an embroidery frame associated therewith, and all of the embroidery frames are generally mechanically interconnected to a frame displacing or control device which moves all of the individual frames according to a desired pattern beneath the corresponding heads to accomplish embroidery patterns simultaneously on multiple pieces of fabric, each of which is positioned beneath one of the heads. This, of course, is a high production arrangement.
Each embroidery frame in a typical multi-head installation includes a pair of hoops (inner and outer). Fabric is held in place between the inner and outer hoops while the embroidering occurs. Obviously, the fabric being held must be of a size at least as large as the puter dimensions of the inner hoop so that it extends into the interface between the two hoops for holding purposes.
Therefore, in the past, the embroidering of small fabric pieces such as pockets has been a problem in that pockets are not of a size generally large enough to be held within the inner and outer hoops. One known way to overcome this problem is by means of performing the embroidery on relatively large pieces of fabric, then cutting the pieces of fabric into the proper small size. However, it can be easily seen that such a technique is extremely wasteful as far as the fabric is concerned, in that a relatively large piece of fabric is necessary merely to hold the fabric in place for the embroidery operation.
One known alternative to this approach is described as the "Hong Kong" method in which the embroidery machine is provided with a single frame plate having a plurality of small apertures therein, each aperture being positioned below one of the embroidery heads, and manipulated all at once by the frame displacing device. This way the small fabric pieces can be attached to the frame and embroidered after they are cut to prevent the waste of material. On the other hand, while fabric waste may be eliminated, production economics cannot be realized because once the embroidery operation is completed, the machine is shut down until all of the fabric pieces can be removed from the adapted plate and new fabric pieces attached thereon. This considerably hampers the speed of the embroidery operation.
Another alternative is shown and described in the U.S. Pat. No. 3,664,288 to von Boden et al. In this approach, a specially designed frame at each head includes means for temporarily holding smaller fabric pieces thereto than could be attached to conventional hoops. While fabric waste is eliminated, there is still the problem that at the end of the embroidery operation, one set of completed fabric pieces must be removed from the frame beneath each head and new fabric pieces properly positioned thereunder, which is relatively time consuming.
In the present invention, however, small cut pieces may be embroidered while achieving production economics. A flat adapter plate is secured to the undersurface of a male ring member, which plate has a clearance aperture therein for passage of the embroidery needle to the fabric. The small fabric pieces are then merely taped or secured by some similar device to the rear or undersurface thereof. The male member is then merely laid into a female receiving opening in a board or fixture which is attached to the machine frame displacing device and the fabric pieces are thus presented to the embroidery head. In such an arrangement, while the embroidery operation is commencing with one set of male rings in the fixture, a second set of inner hoops is having a new set of fabric pieces attached thereto. At the end of the embroidery operation, the operator merely removes one set of inner hoops and lays in a second set of inner male rings to which the fabric pieces have already been attached. Thus, the down time of the machine is kept to a minimum, so that production can be significantly enhanced.
In the preferred embodiments, the undersurface of the adapter plate is preferably formed from a teflon material so that should a needle inadvertently engage the plate no damage will occur.
It is therefore an object of the present invention to provide an improved fabric holding device for positioning small fabric pieces on multi-head embroidery machines.
It is another object of the present invention to provide a fabric securing device which minimizes the down time of the embroidery machine between successive embroidery operations.